JPH08305299A - Display system for vehicle - Google Patents

Abstract

PURPOSE: To prevent dynamic distortion and to greatly reduce the distortion of an actual image of image information as seen from each side by specifying the angle of an image-forming surface to a horizontal plane, in a system in which the actual image of the image information is displayed on the image-forming surface via a focusing optical system. CONSTITUTION: The windshield 4 of a vehicle is in a raised position at which it is at 50 deg. or more to a horizontal plane. A part 9 of the windshield 4 is provided with an image-forming surface 1, the image-forming surface 1 also being at an angle of 50 deg. or more to the horizontal plane. A light-emitting display device 2 from which image information to be displayed is emitted as light is provided below the windshield 4, and a focusing optical system 3 is placed between the light-emitting display device 2 and the windshield 4 so that the light from the light-emitting display device 2 is focused on the image-forming surface 1 provided on the part 9 of the windshield 4. Since the actual image of the image information emitted from the light-emitting display device 2 as light is displayed on the image-forming surface 1 via the focusing optical system 3, dynamic distortion does not occur, and with the image-forming surface 1 at an angle of 50 deg. or more to the horizontal plane, distortion as seen from each side can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle display system, and more particularly to a vehicle display for displaying necessary information such as speed to a driver through a window glass of a vehicle such as a vehicle, a ship or an aircraft. Regarding the system.

[0002]

2. Description of the Related Art A head-up display (hereinafter referred to as HUD) has recently been used as a method of displaying information to a driver in a vehicle. This is because the optical information emitted from a light emitting display device such as a liquid crystal display device is reflected toward the driver by a combiner including a half mirror and a hologram provided on the windshield to be displayed in front of the windshield. By creating a virtual image, the driver can read information from the displayed virtual image with almost no movement of the line of sight from the driving state.

In particular, a hologram using a hologram as a combiner is capable of diffracting optical information toward a driver and forming an image at an arbitrary position, and it has a high brightness without impairing the foreground brightness. It is effective as a combiner for HUD because it has a characteristic that a display virtual image can be obtained.

An example of the HUD using the hologram as the combiner is shown in FIG. Light emitted from the light-emitting display device 2 is diffracted by the hologram 30 toward the driver 6, and a display virtual image 31 formed in front of the windshield 4 is observed.

[0005]

However, in the above-described conventional method, since the driver 6 (observer) observes a virtual image, the virtual display image observed by the driver 6 when the eyes move. Not only the position of the display image 31 changes, but also the distortion of the display virtual image 31 changes, which causes a problem that the shape of the display virtual image 31 appears variously deformed during driving.

In particular, when the ratio (magnification) of the size of the display element image to be displayed and the display virtual image thereof is increased, the change in the distortion of the display virtual image (dynamic distortion) observed during operation is large. Therefore, there is a problem that not only the observer feels uncomfortable, but also the visibility of the display is remarkably lowered, and the safety problem is increased.

Therefore, in order to solve such a problem, as shown in FIG. 9, a partially diffusing image plane 37 is provided under the windshield 4, and the image plane 37 emits light. It has been proposed to image the light of a display device to display a real image 32.

By displaying the real image 32 in this manner, the above-mentioned problem of dynamic distortion is solved, but the following problem newly occurs. That is, since the lower portion of the windshield 4 of the passenger car overlaps with the steering wheel 39 in front of the driver, the display portion provided with the image plane 37 is the lower portion of the windshield 4 near the middle of the driver's seat and the passenger seat. Becomes Since the windshield 4 of a passenger car is generally installed at an angle of 20 ° to 40 ° with respect to the horizontal plane, when the driver sees the real image 32, the image extremely tilted in the vertical direction is seen from the side. It will be a matter. As a result, the real image 32 is greatly moved forward and is also greatly inclined to the left, and the image distortion is greatly increased. Even if the shape of the image emitted from the light emitting display device is corrected so that it is tilted to the right in advance in order to cancel the distortion in the left-right direction, this time when viewed from the passenger's seat, it is much more right. There was a problem of tilting in the direction.

It is an object of the present invention to solve the above-mentioned drawbacks of the prior art and to provide a vehicle display system capable of displaying a real image with less distortion.

[0010]

The present invention has been made in view of the above-mentioned problems, and image information emitted as light from the image information emitting means is incident on the image forming optical system, and the image forming optical system is provided. A vehicle display system for displaying a real image of the image information on an image forming surface via a display, wherein the angle of the image forming surface with respect to a horizontal plane is 50 ° or more. .

In the present invention, since the real image of the image information emitted as light from the image information emitting means is displayed on the image forming surface via the image forming optical system, no dynamic distortion occurs. Since the angle of the image plane with respect to the horizontal plane is 50 ° or more, the distortion when the real image is viewed from the side can be reduced.

The image plane may be provided separately from the window glass of the vehicle, but it is preferably provided on a part of the window glass of the vehicle having an angle of 50 ° or more with the horizontal plane. .

And, preferably, the window glass is a windshield.

The present invention can be preferably applied when the windshield is a windshield of a truck, a bus, a rail car or a ship.

In this case, since the angle of the windshield with respect to the horizontal plane is usually 90 ° or less, the upper limit of the angle of the image plane with respect to the horizontal plane is 90 °.

The image plane is 30 cm from the edge of the windshield.
It is preferable to provide it in the peripheral portion.

More preferably, the image plane is provided on the upper peripheral portion or the lower peripheral portion of the windshield.

When the windshield is a windshield of a truck or a bus, it is preferable that the image plane is provided on the lower peripheral portion of the windshield near the front of the driver's seat.

The image plane is preferably a light diffusion layer.

The light diffusing layer is a light diffusing layer for diffusing light by its own minute irregularities, or a reflection hologram recording a light diffusing layer for diffusing light by its own minute irregularities. It is preferable.

Preferably, the colored layer is arranged outside the light diffusion layer.

The image plane may also be a light-shielding portion provided on the periphery of the window glass. It is preferable to provide a light diffusing layer on the light shielding portion.

The present invention will be described in detail below with reference to the drawings. Here, the present invention will be described by taking an on-vehicle head-up display (HUD) as an example.

FIG. 1 is a conceptual diagram of an in-vehicle display system according to the present invention, in which a windshield 4 of a vehicle is raised and placed,
Set at 50 ° or more with respect to the horizontal plane. If the vehicle to which the present invention is applied is a truck, a bus, a railroad vehicle or a ship, especially a truck or a bus, the windshield 4 thereof has an angle of 50 ° or more with respect to the horizontal plane, and thus the present invention is preferably applied. it can. An image plane 1 is provided on a part of the windshield, and the image plane 1 also forms an angle of 50 ° or more with the horizontal plane. A light emitting display device 2 is provided below the windshield 4 of the vehicle. The light emitting display device 2 is, for example, a device that emits light emitted from a light source as image information to be displayed by passing through a display body which is a shutter group of light such as a liquid crystal display element. An image forming optical system 3 such as a lens is arranged between the light emitting display device 2 and the windshield 4, and light from the light emitting display device 2 is formed on an image forming surface 1 provided on a part 9 of the windshield 4. Try to image. The formed real image is visually recognized at the observation position of the observer 5.
As the imaging optical system 3, it is possible to use a lens or the like that uses refraction of light, a concave mirror that uses reflection, a hologram that uses diffraction, and other optical systems that can substantially form a real image can be used. Is. It is also possible to combine them. Further, the image forming optical system 3 can be integrated with the light emitting display device 2.

Although the real image can be visually recognized even if the windshield 4 itself is used as the image forming surface 1, it is preferable to use a light scattering layer having a function of diffusing (scattering) light. This is because the range in which the real image can be visually recognized is widened by scattering the light, and the visibility can be improved.

As the light-scattering layer, a light-diffusing layer which diffuses light due to its own minute irregularities can be used. As such a light diffusing layer, it is suitable to use a diffusing plate such as frosted glass which has fine irregularities on the surface and can serve as a screen which diffuses light to some extent. Further, this diffusion effect is not limited to frosted glass as long as it has a substantially diffused reflection effect, and a film-like one having fine irregularities on the surface can be stretched over the windshield 4. It is also possible to sandwich and enclose it between two pieces of glass. It is also possible to coat the windshield 4 with a substance having a substantial diffusion effect.

As the light diffusing layer, it is also possible to use a reflection hologram in which a light diffusing layer for diffusing light by its own minute unevenness is recorded.

On the outside of the light scattering layer having a diffusion effect,
By arranging a colored layer such as a dark film, an image with high contrast can be obtained even when the outside of the vehicle is bright.

The position where the image plane 1 is provided is preferably the peripheral portion 8 of the windshield such as the outside of the broken line 8'in FIG.
If the image is formed in a part near the center of the windshield 4 and the diffusion effect is added to the glass, it becomes difficult to visually recognize the foreground. Therefore, the peripheral portion within 30 cm from the peripheral edge of the windshield 4 is preferable.
Further, by providing the image plane 1 on the lower peripheral portion of the windshield to perform the display, the visibility of the hood of the car is obstructed, but the obstruction of the visual recognition of the foreground that substantially hinders driving is eliminated. preferable. Further, even if the image plane 1 is provided on the upper peripheral portion of the windshield to perform the display, the visual hindrance of the foreground that would substantially hinder the driving is similarly eliminated, which is preferable.

Further, as the place where the image plane 1 is provided, the light-shielding paste (black paste) portion 10 coated on the peripheral portion of the windshield 4 and the light-shielding paste lower portion 19 of the light-shielding paste portion 10 are suitable. (See FIG. 2). The color of the light-shielding paste is not limited to black, and gray may be used without any problem.
Further, a light scattering layer for adding a diffused reflection effect of light may be arranged on the image forming surface, or it can be visually recognized by scattering of the light shielding paste itself. This is because when the image is formed on the transparent glass portion, the contrast of the displayed image is lowered and it is difficult to visually recognize it when the outside of the vehicle is bright.

The windshield 4 stands up to 50 ° or more with respect to the horizontal plane, and the image plane 1 is provided on a part of the windshield. As a result, as shown in FIG. 3, the driver 6 and the passenger 7
From any of the above, the real image displayed on the image plane 1 has little distortion.

Further, generally, in the case of a truck or a bus, as shown in FIG. 4, the steering wheel 39 and the lower portion 15 of the windshield 4 do not overlap with each other when viewed from the driver, so that the image plane 1 is formed in front of the driver. Can be provided and displayed. In that case,
The driver sees almost no distortion.

Next, the reflection hologram used as the light diffusion layer will be described. As the reflection type hologram, it is suitable to use one in which an object having fine irregularities is recorded, such as a diffusion plate (frosted glass).
This is because the real image formed on the reflection hologram can be visually recognized as if it is reflected on the frosted glass screen on the windshield. This is because there is no light and the light is efficiently scattered in the direction of the observer, and the visibility can be improved.

The wavelength used for exposing the reflection hologram may be a single wavelength, but it is also possible to create the reflection hologram by exposing the reflection hologram with lasers of a plurality of wavelengths simultaneously or sequentially. Furthermore, it is naturally possible to superimpose a plurality of holograms. It is preferable to use a hologram that has been exposed in multiple colors as described above, since the display colors can be multicolored.

Such a reflection hologram 18 is shown in FIG.
As shown in FIG. 3, it can be obtained by generating laser light from two laser light sources (12, 13) and exposing the reflection hologram 18. At this time, the laser light source (12, 1
At least one of 3) and the reflection hologram 18
The diffusion plate 1 is provided by arranging the diffusion plate 14 between
It is possible to create the reflection hologram 18 in which 4 is recorded.

The exposure arrangement is not limited to this example, and the reflection hologram 18 substantially equivalent to this example can be obtained by various methods. For example, diffuser 1
4 is a reflective type instead of a transmissive type, or a single laser light source (12, 13) is used.
It is also possible to place a reflection type diffusion plate on the side opposite to the light source for exposure.

Further, the incident angle θ2 from the center of the light emitting display device to the center of the hologram at which the light beam from the light emitting display device is incident toward the reflection type hologram 18, and the reflection hologram 1.
By making the angle of diffraction θ1 from the center of the reflection hologram of the real image diffracted by 8 and visually recognized by the observer different, the light diffracted by the reflection hologram 18 can be visually recognized and the specular reflection light on the glass surface. This is preferable because the position where the image is to be visually recognized is different, and the glare of the specular reflection image is eliminated.

The image information displayed in the present invention is appropriately selected according to its display application, and examples thereof include a vehicle speedometer, a tachometer, various warning lamps, and navigation information. .

In the present invention, the observer who observes the displayed real image is mainly the driver of the vehicle, but in some cases, it may include the passenger in the passenger seat, other passengers, and all of them. it can.

In the above, the HUD has been described as an example of the field to which the present invention is applied, but it is naturally possible to apply it to other vehicle display systems.

The image information emitting means in the present invention is a light emitting display device which emits image information as light. For example, a hot cathode tube (HCT) is provided on a display body comprising a light receiving display element which is a so-called light shutter such as a liquid crystal display element. ), A fluorescent display tube (VF), a halogen lamp, an LED and the like.

As the liquid crystal display element, a transmission type twisted nematic type liquid crystal display element, a super twisted nematic type liquid crystal display element or the like can be preferably used.

Further, the light source itself may be patterned and arranged without using the light receiving display element to generate specific information as light.

[0044]

Embodiments of the present invention will be described below.

(Embodiment 1) As shown in FIG. 6, a milky white film 17 is enclosed in a laminated glass as a diffusion plate on the lower part 1 of a windshield 4 of a truck, and the light emitting display device 2 is about 300 mm from the milky white film 17. It was placed in a distant position.
The focal length is about 40 mm at a position about 50 mm from the light emitting display device 2.
A mm convex lens 3 was arranged. The windshield 4 of the truck forms an angle of 50 ° or more with the horizontal plane.

As a result, a real image was formed on the milky white film 17 in the windshield 4. The magnification at that time was about 5 times. The observer could clearly read the formed real image with little distortion. Further, since the display position is below the windshield 4, it does not hinder the visual recognition of the foreground, which hinders driving.

(Embodiment 2) As shown in FIG. 7, a reflection hologram 18 is used as a laminated glass on the inner surface of the lower end of the windshield 4 of the truck which is coated with the black paste 11 near the front of the driver. Enclosed. The light emitting display device 2 was placed at a position about 300 mm away from the reflection hologram 18. A convex lens 3 having a focal length of about 40 mm was arranged at a position of about 50 mm from the light emitting display device 2. The windshield 4 of the truck forms an angle of 50 ° or more with the horizontal plane.

As a result, a real image was formed on the reflection hologram 18 at the lower end of the windshield 4. The magnification at that time was about 5 times. The driver (observer) was able to clearly read the formed real image. Further, since the display position is below the windshield 4, it does not hinder the visual recognition of the foreground, which hinders driving. Further, even when the foreground was bright, the real image was clearly visible on the black paste 11.

[0049]

According to the present invention, image information emitted as light from the image information emitting means is incident on the image forming optical system,
In a vehicle display system for displaying a real image of image information on an image forming surface via an image forming optical system, since the angle of the image forming surface with respect to the horizontal plane is 50 ° or more, no dynamic distortion occurs, and this real image is displayed. The distortion when viewed from the side can be greatly reduced.

If this image forming surface is provided on a part of the windshield such as a truck or a bus, it can be displayed in front of the driver, so that the distortion can be almost eliminated.

[Brief description of drawings]

FIG. 1 is a conceptual cross-sectional view for explaining a vehicle display system of the present invention.

FIG. 2 is a diagram for explaining display positions of the vehicle display system of the present invention.

FIG. 3 is a diagram for explaining display positions of the vehicle display system of the present invention.

FIG. 4 is a diagram for explaining display positions of the vehicle display system of the present invention.

FIG. 5 is a diagram showing a hologram exposure method used in the vehicle display system of the present invention.

FIG. 6 is a conceptual cross-sectional view for explaining an example of the vehicle display system of the present invention.

FIG. 7 is a conceptual cross-sectional view for explaining another example of the vehicle display system of the present invention.

FIG. 8 is a side view for explaining a conventional vehicle display system.

FIG. 9 is a diagram for explaining a problem when a real image is displayed on a passenger car display system.

[Explanation of symbols]

 1: Imaging plane 2: Light-emitting display device 3: Imaging optical system 4: Windshield 5: Observer 6: Driver 7: Passenger passenger 8: Windshield periphery 9: Part of windshield 10: Shading Paste part 11: Black paste 15: Windshield lower part 17: Milky white film 18: Hologram 19: Light-shielding paste part lower part 30: Hologram 31: Displayed virtual image 32: Real image 37: Image plane 39: Handle

Claims (4)

[Claims] 1. A vehicle display system in which image information emitted as light from image information emitting means is incident on an image forming optical system and a real image of the image information is displayed on the image forming surface via the image forming optical system. A vehicle display system characterized in that the angle of the image plane with respect to the horizontal plane is 50 ° or more. 2. The vehicle display according to claim 1, wherein the image forming surface is provided on a part of a windshield of a vehicle, the windshield having an angle of 50 ° or more with a horizontal plane. system. 3. The vehicle display system according to claim 1 or 2, wherein the image forming surface comprises a reflection hologram in which a light diffusing layer for diffusing light is recorded by its own minute irregularities. 4. The vehicle display system according to claim 1, wherein a colored layer is arranged outside the image plane.